Ring off a ring ! Help please

[Jordan Henley]

Hi, I know you can’t put a ring off a ring, you should join a cable in the back box of a socket, take it to your new socket, then continue the ring until you get back to your original socket

But I don’t know the reasoning why you can’t make a figure of 8 ring main if you like,
Could someone help me please
Many thanks

 

[M-Ty]

It puts a large load at one point instead of distributing the total load reasonably around the ring, with the possibility of overloading one leg if not near the centre of the ring. Similar to taking a single unfused spur in 4 or more sq.mm off to feed lots of sockets or, say, a cooker or shower.

 

[Wilko]

Hi Jordan and welcome.
As per @M-Ty, its a point load on the original ring with a bunch of outlets. So you’d need to connect it by a 13A fuse. If you preserved the original ring the 32A rating extends to the new bit, as long as the new ring meets earth loop impedance limits.

 

[ferg]

Mathematically I think it's no different to a lollipop circuit but testing would be a pain in the rear and I can't think of a single instance where extending the ring wasn't the easiest option.

I'll be honest I can't see the need or use for it.

 

[cliffed]

Also why would you wanna do that.
If I’m adding 3/4 sockets of ring I usually come off to a unswitced spur then radial to power points,obviously in local area.some of these new houses are a mare to add anything new,ie: chipboard floors,Also your not the disturbing the ring as such,

 

[Richard Burns]

A diagram to show the potential for overload as described by M-Ty using some possible current loads (obviously chosen to overload the cable)
You would have to work at it to overload but it is more likely and you would not need to overload the MCB to do it.

 

[Tony Reidy]

Hi, I know you can’t put a ring off a ring, you should join a cable in the back box of a socket, take it to your new socket, then continue the ring until you get back to your original socket

But I don’t know the reasoning why you can’t make a figure of 8 ring main if you like,
Could someone help me please
Many thanks

First of all have you tested the circuit you wish to extend are the readings acceptable

 

[mart spark]

Although not dangerous in theory if there were a break in one of the legs after the cross over this would not show on an end to end test on a c.u. or d.b. therefore leaving one leg liable to overload. Or so my understanding leads me to believe.

 

[cliffed]

Just don’t do it

 

[Octopus]

Very common to see this poor design and install in DIY "jobs"

I always recommend improvements ...........

 

[Jordan Henley]

Thanks guys! I just passed my AM2 and completed my NVQ, after telling my dad he’s extended the ring in the wrong way, he still knows best! I just didn’t know the reasoning behind it!
Thanks for your help and welcoming me onto this site

 

[PEG]

Thanks guys! I just passed my AM2 and completed my NVQ, after telling my dad he’s extended the ring in the wrong way, he still knows best! I just didn’t know the reasoning behind it!
Thanks for your help and welcoming me onto this site

....It always touches me,when i see a family sharing such personal troubles...

 

[GeorgeCooke]

Hi, I know you can’t put a ring off a ring,

You can. Normally called a lollypop circuit.

 

[Deleted member 9648]

You can. Normally called a lollypop circuit.

A lollipop circuit is a ring extended from a suitably rated radial, often a redundant 6.0mm cooker circuit in a kitchen for example. That's a totally different beast to a 'ring off a ring'.

 

[FatAlan]

Thanks guys! I just passed my AM2 and completed my NVQ, after telling my dad he’s extended the ring in the wrong way, he still knows best! I just didn’t know the reasoning behind it!
Thanks for your help and welcoming me onto this site

Get you dad signed up on here quick.